The genetically determined Lp(a) lipoprotein whose specific apoprotein evolved from plasminogen exhibits association with atherosclerotic/thrombotic diseases including coronary heart disease (CHD). People with an Lp(a) lipoprotein concentration corresponding to the top quartile in the healthy population have a significantly increased CHD risk compared with those with a lower value, and the risk in the top decile appears to be particularly high. However, a very low Lp(a) lipoprotein level may also cause disadvantage with respect to CHD and longevity. Lp(a) lipoprotein may compromise thrombolytic processes through molecular mimicry and in vitro it stimulates vascular cells to cell division, The normal function of Lp(a) lipoprotein is unknown. It could be related to repair processes, Preliminary evidence suggests that Lp(a) lipoprotein may be involved in vascular processes in the placenta. It has been reported that Lp(a) lipoprotein increases following myocardial infarction in a way suggesting that it could possess characteristics of an acute phase reactant. In view of the strikingly high heritability of Lp(a) lipoprotein, this would a priori be unlikely. We have not been able to confirm a significant increase in Lp(a) lipoprotein following myocardial infarction. Several commercially available test kits are of a doudtful quality. At present, a highly needed, international effort at standardizing Lp(a) lipoprotein measurements is taking place.
